EAS BUSINESS… Properties, Astronomers Must Contend with Our Position Within the Galaxy, Which Requires Disentangling the Various Constituent Parts
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Constructing a Galactic Coordinate System Based on Near-Infrared and Radio Catalogs
A&A 536, A102 (2011) Astronomy DOI: 10.1051/0004-6361/201116947 & c ESO 2011 Astrophysics Constructing a Galactic coordinate system based on near-infrared and radio catalogs J.-C. Liu1,2,Z.Zhu1,2, and B. Hu3,4 1 Department of astronomy, Nanjing University, Nanjing 210093, PR China e-mail: [jcliu;zhuzi]@nju.edu.cn 2 key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education, Nanjing 210093, PR China 3 Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, PR China 4 Graduate School of Chinese Academy of Sciences, Beijing 100049, PR China e-mail: [email protected] Received 24 March 2011 / Accepted 13 October 2011 ABSTRACT Context. The definition of the Galactic coordinate system was announced by the IAU Sub-Commission 33b on behalf of the IAU in 1958. An unrigorous transformation was adopted by the Hipparcos group to transform the Galactic coordinate system from the FK4-based B1950.0 system to the FK5-based J2000.0 system or to the International Celestial Reference System (ICRS). For more than 50 years, the definition of the Galactic coordinate system has remained unchanged from this IAU1958 version. On the basis of deep and all-sky catalogs, the position of the Galactic plane can be revised and updated definitions of the Galactic coordinate systems can be proposed. Aims. We re-determine the position of the Galactic plane based on modern large catalogs, such as the Two-Micron All-Sky Survey (2MASS) and the SPECFIND v2.0. This paper also aims to propose a possible definition of the optimal Galactic coordinate system by adopting the ICRS position of the Sgr A* at the Galactic center. -
Eclipse Newsletter
ECLIPSE NEWSLETTER The Eclipse Newsletter is dedicated to increasing the knowledge of Astronomy, Astrophysics, Cosmology and related subjects. VOLUMN 2 NUMBER 1 JANUARY – FEBRUARY 2018 PLEASE SEND ALL PHOTOS, QUESTIONS AND REQUST FOR ARTICLES TO [email protected] 1 MCAO PUBLIC NIGHTS AND FAMILY NIGHTS. The general public and MCAO members are invited to visit the Observatory on select Monday evenings at 8PM for Public Night programs. These programs include discussions and illustrated talks on astronomy, planetarium programs and offer the opportunity to view the planets, moon and other objects through the telescope, weather permitting. Due to limited parking and seating at the observatory, admission is by reservation only. Public Night attendance is limited to adults and students 5th grade and above. If you are interested in making reservations for a public night, you can contact us by calling 302-654- 6407 between the hours of 9 am and 1 pm Monday through Friday. Or you can email us any time at [email protected] or [email protected]. The public nights will be presented even if the weather does not permit observation through the telescope. The admission fees are $3 for adults and $2 for children. There is no admission cost for MCAO members, but reservations are still required. If you are interested in becoming a MCAO member, please see the link for membership. We also offer family memberships. Family Nights are scheduled from late spring to early fall on Friday nights at 8:30PM. These programs are opportunities for families with younger children to see and learn about astronomy by looking at and enjoying the sky and its wonders. -
Daniel Huber
Asteroseismology & Exoplanets: A Kepler Success Story Daniel Huber SETI Institute / NASA Ames Research Center U Chicago Astronomy Colloquium April 2014 Collaborators Bill Chaplin, Andrea Miglio, Yvonne Elsworth, Tiago Campante & Rasmus Handberg (Birmingham) Jørgen Christensen-Dalsgaard, Hans Kjeldsen, Victor Silva Aguirre (Aarhus) Tim Bedding & Dennis Stello (Sydney) Ron Gilliland (PSU), Sarbani Basu (Yale), Steve Kawaler (Iowa State), Travis Metcalfe (SSI), Jaymie Matthews (UBC), Saskia Hekker (Amsterdam), Marc Pinsonneault & Jennifer Johnson (OSU), Eric Gaidos (Hawaii) Tom Barclay, Jason Rowe, Elisa Quintana & Jack Lissauer (NASA Ames / SETI) Josh Carter, Lars Buchhave, Dave Latham, Ben Montet & John Johnson (Harvard) Dan Fabrycky (Chicago) Josh Winn, Kat Deck & Roberto Sanchis-Ojeda (MIT) Andrew Howard, Howard Isaacson & Geoff Marcy (Hawaii, Berkeley) The Kepler Space Telescope • launched in March 2009 • 0.95 m aperture • 42 CCD’s , 105 sq deg FOV Borucki et al. (2008), Koch et al. (2010) Kepler Field of View Kepler Orbit Kepler obtained uninterrupted high-precision photometry of ~> 150,000 stars for 4 years to search for transiting exoplanets Asteroseismology in a Nutshell AstEroseismology? AstEroseismology? unnamed author, sometime in 1995 What causes stellar oscillations? Oscillations in cool stars are driven by turbulent surface convection (opacity in hot stars) Radial Order n displacement center surface number of nodes from the surface to the center of the star Spherical Degree l l = 0 Spherical Degree l l = 2 l = 0 Δν ~ 135 µHz for the Sun sound speed cs -1 3 1/2 Δν = (2 ∫dr/cs) ∝ (M/R ) (ω = n π c / L!) Ulrich (1986) δν ∝ ∫dcs/dr (Age) δν (individual frequencies) sound speed cs -1 3 1/2 Δν = (2 ∫dr/cs) ∝ (M/R ) (ω = n π c / L!) Ulrich (1986) νmax νmax ~ 3000 µHz for the Sun 0.5 -2 0.5 νmax ∝ νac ∝ g Teff ∝ M R Teff Brown et al. -
The Gould Belt
Astrophysics, Vol. 57, No. 4, pp. 583-604, December, 2014. REVIEWS THE GOULD BELT V.V. Bobylev1,2 1Pulkovo Astronomical Observatory, St. Petersburg, Russia 2Sobolev Astronomical Institute, St. Petersburg State University, Russia AbstractThis review is devoted to studies of the Gould belt and the Local system. Since the Gould belt is the giant stellar-gas complex closest to the sun, its stellar component is characterized, along with the stellar associations and diffuse clusters, cold atomic and molecular gas, high-temperature coronal gas, and dust contained in it. Questions relating to the kinematic features of the Gould belt are discussed and the most interesting scenarios for its origin and evolution are examined. 1 Historical information Stars of spectral classes O and B that are visible to the naked eye define two large circles in the celestial sphere. One of them passes near the plane of the Milky Way, while the second is slightly inclined to it and is known as the Gould belt. The minimum galactic latitude of the Gould belt is in the region of the constellation Orion, and the maximum, in the region of Scorpio-Centaurus. Herschel noted [1] that some of the bright stars in the southern sky appear to be part of a separate structure from the Milky Way with an inclination to the galactic equator of about 20◦. Commenting on the features of the distribution of stars in the Milky Way, Struve [2] independently noted that the stars that form the largest densifications on the celestial sphere can lie in two planes with a mutual inclination of about 10◦. -
A Temperate Rocky Super-Earth Transiting a Nearby Cool Star Jason A
LETTER doi:10.1038/nature22055 A temperate rocky super-Earth transiting a nearby cool star Jason A. Dittmann1, Jonathan M. Irwin1, David Charbonneau1, Xavier Bonfils2,3, Nicola Astudillo-Defru4, Raphaëlle D. Haywood1, Zachory K. Berta-Thompson5, Elisabeth R. Newton6, Joseph E. Rodriguez1, Jennifer G. Winters1, Thiam-Guan Tan7, Jose-Manuel Almenara2,3,4, François Bouchy8, Xavier Delfosse2,3, Thierry Forveille2,3, Christophe Lovis4, Felipe Murgas2,3,9, Francesco Pepe4, Nuno C. Santos10,11, Stephane Udry4, Anaël Wünsche2,3, Gilbert A. Esquerdo1, David W. Latham1 & Courtney D. Dressing12 15 16,17 M dwarf stars, which have masses less than 60 per cent that of Ks magnitude and empirically determined stellar relationships , the Sun, make up 75 per cent of the population of the stars in the we estimate the stellar mass to be 14.6% that of the Sun and the stellar Galaxy1. The atmospheres of orbiting Earth-sized planets are radius to be 18.6% that of the Sun. We estimate the metal content of the observationally accessible via transmission spectroscopy when star to be approximately half that of the Sun ([Fe/H] = −0.24 ± 0.10; the planets pass in front of these stars2,3. Statistical results suggest 1σ error), and we measure the rotational period of the star to be that the nearest transiting Earth-sized planet in the liquid-water, 131 days from our long-term photometric monitoring (see Methods). habitable zone of an M dwarf star is probably around 10.5 parsecs On 15 September 2014 ut, MEarth-South identified a potential away4. A temperate planet has been discovered orbiting Proxima transit in progress around LHS 1140, and automatically commenced Centauri, the closest M dwarf5, but it probably does not transit and high-cadence follow-up observations (see Extended Data Fig. -
76 Minor Planet Bulletin 45 (2018) TWENTY-ONE ASTEROID LIGHTCURVES at ASTEROIDS OBSERVERS (OBAS)
76 TWENTY-ONE ASTEROID LIGHTCURVES needed confirmation. All the targets were selected from the AT ASTEROIDS OBSERVERS (OBAS) - MPPD: Collaborative Asteroid Lightcurve (CALL) website at NOV 2016 - MAY 2017 http://www.minorplanet.info/call.html, paying special attention to keeping the asteroid’s magnitude within reach of the telescopes Vicente Mas, G. Fornas being used. We tried to observe asteroids at a phase angle of less CAAT, Centro Astronómico del Alto Turia, SPAIN than 14°, but this was not always possible. [email protected] Images were measured using MPO Canopus (Bdw Publishing) Juan Lozano with a differential photometry technique. For more information Elche Observatory, Alicante, SPAIN about methods and techniques used, see Aznar Macias et al. (2015). Table II lists the individual results along with the range of Onofre Rodrigo dates for the observations and the number of nights that Bétera Observatory, Valencia, SPAIN observations were made. A. Fornas 589 Croatia, Observed on nine nights from 2016 Nov to 2017 Jan. Oropesa Observatory, Castellón, SPAIN Period: 24.73 ± 0.013 h. Amplitude: 0.47 mag. This result is consistent with Behrend (2013), who found 24.821 h, but not with A. Carreño Waszczak et al. (2015) who found 16.385 h. Zonalunar Observatory,Valencia, SPAIN 593 Titania. Observed during five nights 2017 Apr. Period: 9.930 Enrique Arce ± 0.009 h. Amplitude: 0.21 mag. This period is consistent with Vallbona Observatory, Valencia, SPAIN Zappala (1983, 9.89 h), Harris (1989, 9.899 h), and Behrend (2017, 9.8968 h). Pedro Brines TRZ Observatory, Valencia, SPAIN 728 Leonisis. Observed on two nights in 2017 March-April. -
Strange and Terrible Wonders: Climate Change In
STRANGE AND TERRIBLE WONDERS: CLIMATE CHANGE IN THE EARLY MODERN WORLD A Dissertation by CHRISTOPHER RYAN GILSON Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Chair of Committee, Chester S. L. Dunning Committee Members, R. J. Q. Adams Joseph G. Dawson III Peter J. Hugill Head of Department, David Vaught August 2015 Major Subject: History Copyright 2015 Christopher R. Gilson ABSTRACT The study of climate and climatic change began during the Little Ice Age of the early modern world. Beginning in the sixteenth century, European clerics, scientists, and natural philosophers penned detailed observations of the era’s unusually cool and stormy weather. Scouring the historical record for evidence of similar phenomena in the past, early modern scholars concluded that the climate could change. By the eighteenth century, natural philosophers had identified at least five theories of climatic change, and many had adopted some variation of an anthropogenic explanation. The early modern observations described in this dissertation support the conclusion that cool temperatures and violent storms defined the Little Ice Age. This dissertation also demonstrates that modern notions of climate change are based upon 400 years of rich scholarship and spirited debate. This dissertation opens with a discussion of the origins of “climate” and meteorology in ancient Greek and Roman literature, particularly Aristotle’s Meteorologica. Although ancient scholars explored notions of environmental change, climate change—defined as such—was thought impossible. The translation and publication of ancient texts during the Renaissance contributed to the reexamination of nature and natural variability. -
Asteroseismology
Asteroseismology Gerald Handler Copernicus Astronomical Center, Bartycka 18, 00-716 Warsaw, Poland Email: [email protected] Abstract Asteroseismology is the determination of the interior structures of stars by using their oscillations as seismic waves. Simple explanations of the astrophysical background and some basic theoretical considerations needed in this rapidly evolving field are followed by introductions to the most important concepts and methods on the basis of example. Previous and potential applications of asteroseismology are reviewed and future trends are attempted to be foreseen. Introduction: variable and pulsating stars Nearly all the physical processes that determine the structure and evolution of stars occur in their (deep) interiors. The production of nuclear energy that powers stars takes place in their cores for most of their lifetime. The effects of the physical processes that modify the simplest models of stellar evolution, such as mixing and diffusion, also predominantly take place in the inside of stars. The light that we receive from the stars is the main information that astronomers can use to study the universe. However, the light of the stars is radiated away from their surfaces, carrying no memory of its origin in the deep interior. Therefore it would seem that there is no way that the analysis of starlight tells us about the physics going on in the unobservable stellar interiors. However, there are stars that reveal more about themselves than others. Variable stars are objects for which one can observe time-dependent light output, on a time scale shorter arXiv:1205.6407v1 [astro-ph.SR] 29 May 2012 than that of evolutionary changes. -
SIAC Newsletter October 2013
SOUTHEASTERN IOWA ASTRONOMY CLUB THE SIDEREAL TIMES OCTOBER 2013 A M EMBER SOCIETY OF THE ASTRONOMICAL LEAGUE CLUB OFFICERS : MINUTES SEPTEMBER 20, 2013 President Jim Hilkin called the meeting to is meeting night. Jim Hilkin gave an up- Executive Committee order with the following members in attend- date on the following maintenance President Jim Hilkin items: some additional dirt was added to Vice President Libby Snipes ance: Judy Smithson, Libby Snipes, Jim Treasurer Vicki Philabaum Wilt, Ray Reineke, Duane Gerling, Claus the east end of the berm to help block Secretary David Philabaum Benninghoven, Dave Philabaum, John Ton- headlights from cars coming from the Chief Observer David Philabaum ey, and Paul Sly. Vicki Philabaum conduct- beach and area E; the viburnum bushes Members-at-Large Claus Benninghoven ed a tour of the facility for a group from on the north side of the classroom were Duane Gerling Great River Christian School during the removed as they were getting too big for Blake Stumpf meeting. Libby moved to approve the the space; Jim has installed cabinet Board of Directors minutes as published, seconded by Jim Wilt, doors and created a storage area in the Chair Judy Hilkin motion passed. Jim Hilkin read the Treasur- Stone-Kelly dome; the new doors for Vice Chair Ray Reineke er's report from Vicki. Checks were written the Prugh-Carver Observatory are in, Secretary David Philabaum for the phone bill and to Ray for the new but there has been no word from SCC Members-at-Large David Martin about painting them so Barngrover's will Blake Stumpf motor for the Fecker telescope. -
Des Ign of Multi-Mission Chemical Propulsion Modules for Planetary Orbiters
,-/ 7 0 26085-6001 -TUOO DES IGN OF MULTI-MISSION CHEMICAL PROPULSION MODULES FOR PLANETARY ORBITERS VOLUME ii: TECHNICAL REPORT 15 AUGUST 1975 Prepared for NASA AMES RESEARCH CENTER ; , under Contract NAS2-8370 (NASA-CR-137790): DESIGN OFIMULTI-ISSION N76-14197 CHEMICAL PROPULSION MODULES FOR PLANETARY 'ORBITERS, VOLUME 2: TECHNICAL REPORT (TRW ;Systems Group) 270 p HC $9.00 CSCL 21H Unclas G3/20 07169 26085-6001 -TUOO DESIGN OF MULTI -MISS ION CHEMICAL- PROPULSION MODULES FOR PLANETARY ORBITERS VOLUME II: TECHNICAL REPORT 15 AUGUST 1975 Prepared for NASA AMES RESEARCH CENTER under 'Contract NAS2-8370 The final report of this study is presented in three volumes: I Summary Report II Technical Report Ii Appendixes Use of Metric and English Units in this Report The results of this study are reported in metric and- English units. ' The metric notation generally is quoted first. However, since in the present transition phase most of the engineering work is still being performed in terms of English units, some of the supporting calcula tions are repoited only in these units. In other instances English units are stated first, with metric units in parentheses, e.g., in reference to a iZ-foot (3. 66-rineter) antenna dish. ii CONTENTS Page 1. INTRODUCTION AND SCOPY; OF STUDY L-1 1.1 Background 1-1 1. 2 Mission Constraints and Performance 1-2 Requ.i rer:ents 1.3 Missions to be Performed by the 1 -3 Multi-Mission Pro:ulsion Mlodules 114 Study Objectives I-, 1. 5 Relation to Previous and Concurrent Studies 1 -5 1.6 Organization of Report 1 -6 2. -
The Handbook of the British Astronomical Association
THE HANDBOOK OF THE BRITISH ASTRONOMICAL ASSOCIATION 2012 Saturn’s great white spot of 2011 2011 October ISSN 0068-130-X CONTENTS CALENDAR 2012 . 2 PREFACE. 3 HIGHLIGHTS FOR 2012. 4 SKY DIARY . .. 5 VISIBILITY OF PLANETS. 6 RISING AND SETTING OF THE PLANETS IN LATITUDES 52°N AND 35°S. 7-8 ECLIPSES . 9-15 TIME. 16-17 EARTH AND SUN. 18-20 MOON . 21 SUN’S SELENOGRAPHIC COLONGITUDE. 22 MOONRISE AND MOONSET . 23-27 LUNAR OCCULTATIONS . 28-34 GRAZING LUNAR OCCULTATIONS. 35-36 PLANETS – EXPLANATION OF TABLES. 37 APPEARANCE OF PLANETS. 38 MERCURY. 39-40 VENUS. 41 MARS. 42-43 ASTEROIDS AND DWARF PLANETS. 44-60 JUPITER . 61-64 SATELLITES OF JUPITER . 65-79 SATURN. 80-83 SATELLITES OF SATURN . 84-87 URANUS. 88 NEPTUNE. 89 COMETS. 90-96 METEOR DIARY . 97-99 VARIABLE STARS . 100-105 Algol; λ Tauri; RZ Cassiopeiae; Mira Stars; eta Geminorum EPHEMERIDES OF DOUBLE STARS . 106-107 BRIGHT STARS . 108 ACTIVE GALAXIES . 109 INTERNET RESOURCES. 110-111 GREEK ALPHABET. 111 ERRATA . 112 Front Cover: Saturn’s great white spot of 2011: Image taken on 2011 March 21 00:10 UT by Damian Peach using a 356mm reflector and PGR Flea3 camera from Selsey, UK. Processed with Registax and Photoshop. British Astronomical Association HANDBOOK FOR 2012 NINETY-FIRST YEAR OF PUBLICATION BURLINGTON HOUSE, PICCADILLY, LONDON, W1J 0DU Telephone 020 7734 4145 2 CALENDAR 2012 January February March April May June July August September October November December Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day Day of of of of of of of of of of of of of of of of of of of of of of of of of Month Week Year Week Year Week Year Week Year Week Year Week Year Week Year Week Year Week Year Week Year Week Year Week Year 1 Sun. -
Vente De 2 Ans Montés Samedi 14 Mai Breeze Le 13 Mai
11saint-cloud Vente de 2 ans montés Samedi 14 mai Breeze le 13 mai en association avec Index_Alpha_14_05 24/03/11 19:09 Page 71 Index alphabétique Alphabetical index NomsNOM des yearlings . .SUF . .Nos LOT NOM LOT ALKATARA . .0142 N(FAB'S MELODY 2009) . .0030 AMESBURY . .0148 N(FACTICE 2009) . .0031 FORCE MAJEUR . .0003 N(FAR DISTANCE 2009) . .0032 JOHN TUCKER . .0103 N(FIN 2009) . .0034 LIBERTY CAT . .0116 N(FLAMES 2009) . .0035 LUCAYAN . .0051 N(FOLLE LADY 2009) . .0036 MARCILHAC . .0074 N(FRANCAIS 2009) . .0037 MOST WANTED . .0123 N(GENDER DANCE 2009) . .0038 N(ABBEYLEIX LADY 2009) . .0139 N(GERMANCE 2009) . .0039 N(ABINGTON ANGEL 2009) . .0140 N(GILT LINKED 2009) . .0040 N(AIR BISCUIT 2009) . .0141 N(GREAT LADY SLEW 2009) . .0041 N(ALL EMBRACING 2009) . .0143 N(GRIN AND DARE IT 2009) . .0042 N(AMANDIAN 2009) . .0144 N(HARIYA 2009) . .0043 N(AMAZON BEAUTY 2009) . .0145 N(HOH MY DARLING 2009) . .0044 N(AMY G 2009) . .0146 N(INFINITY 2009) . .0045 N(ANSWER DO 2009) . .0147 N(INKLING 2009) . .0046 N(ARES VALLIS 2009) . .0149 N(JUST WOOD 2009) . .0048 N(AUCTION ROOM 2009) . .0150 N(KACSA 2009) . .0049 N(AVEZIA 2009) . .0151 N(KASSARIYA 2009) . .0050 N(BARCONEY 2009) . .0152 N(LALINA 2009) . .0052 N(BASHFUL 2009) . .0153 N(LANDELA 2009) . .0053 N(BAYOURIDA 2009) . .0154 N(LES ALIZES 2009) . .0054 N(BEE EATER 2009) . .0155 N(LIBRE 2009) . .0055 N(BELLA FIORELLA 2009) . .0156 N(LOUELLA 2009) . .0056 N(BERKELEY LODGE 2009) . .0157 N(LUANDA 2009) . .0057 N(BLACK PENNY 2009) . .0158 N(LUNA NEGRA 2009) .